1. Field
The subject invention is in the general field of apparatus used by people for exercising. More specifically it is in the field of such apparatus in the use of which the user is supine, resting on a carriage which is movable in the user's head/feet direction on a track assembly comprising one or more rails or tracks. Still more specifically it is in the field of such apparatus in which the motion of the carriage (and user) is under the influence of variable restoring forces provided by springs, shock cords and the like and the motion of the carriage and user is generated by use of the user's legs or arms, particularly by use of the user's leg(s) and foot or feet against structure attached to the track assembly and termed a kickboard.
2. Prior Art
The most applicable prior art known to the inventor of the subject invention is disclosed in U.S. Pat. Nos. 4,706,953 and 4,884,802 issued to him. Both cover exercise apparatus comprising a platform rolling on parallel tracks in a track assembly and a kickplate, termed a panel 21 in U.S. Pat. No. 4,884,802 as shown in FIG. 1 in this disclosure. The user lies supine on the platform with one or more of his or her feet in position to be placed against and apply force to the kickplate to set the platform and user in oscillating motion on the track frame. U.S. Pat. No. 1,950,174 shows prior art apparatus of this type without a kickboard but having tension members between the user's hands and feet and structure mounted on a track assembly.
It has been learned in the use of apparatus of the type shown in FIG. 1 that the location of the points of contact of user's feet while exercising has significant influence on the results and success of use of the apparatus. For example, for dancers wanting to simulate jumping with heels and toes of the feet in contact with a support or for people with certain coordination difficulties it is helpful to position the kickboard low, i.e. relatively close to the plane of the parallel tracks so that the points of contact of feet on the kickboard are also low. Otherwise, for athletes working to increase their jumping ability with their heels unsupported (i.e. not in contact with the kickplate) it is useful to position the kickplate high so that the contact points of feet on the kickboard are further away from the plane of the track assembly.
It has also been learned that the utility of the subject type exercise apparatus is extended by arranging for the user to be able to activate the apparatus by pulling on the kickplate. Such an arrangement requires that the kickplate be positioned at the end of the track assembly opposite from the end at which it is attached for activation by pushing and by providing attachment points on the kickplate for pulling (negative force) apparatus (shoes or harnesses) worn on the user's feet.
Accordingly, the prime objective of the subject invention is to provide apparatus of the described type having an adjustable kickplate. Another objective is that the kickplate construction and adjustment enable use of the exercise apparatus using negative force activation. Other objectives are that the kickplate and its adjustment means be of simple construction and simple to operate relative to the effectiveness of the adjustments.